Kinetic patterns and optimization of the process of concentration by freezing the blood of cattle

Abstract

The urgency of the use of blood components as a raw material for the production of products from it that contribute to the prevention and treatment of iron deficiency states is beyond doubt. In addition, protein compounds in the blood of cattle have a high digestibility of the human body, and the complex of essential amino acids determines its attractiveness as an additive in the development of a wide range of meat products. The only possible way at present to thicken thermo labile blood compounds is cryoconcentration, carried out in a temperature range close to the cryoscopy temperature. The kinetic features of cryoconcentration of cattle blood were investigated on an experimental apparatus of cyclic action. It is shown that the conditions of cryoconcentration are determined by the boiling point of the refrigerant in the evaporator of the installation, the flow rate of the original blood washing the heat exchange surface and the content of soluble compounds in the initial liquid. Experimental data are presented in the form of growth curves of frozen ice on the heat exchange surface with an area of 0.2 m2. Using mathematical planning methods, equations are obtained that describe the amount of ice frozen for 1 hour per unit of surface area of the freezing plant, the specific energy input for freezing one kilogram of ice, and the dry matter content of the blood in the solution obtained by melting the frozen ice. The solved problem of optimizing the process of blood cryoconcentration made it possible to find rational intervals for changing the operating parameters of the freezing plant, ensuring the maximum amount of frozen ice, minimal energy costs and minimal content of soluble substances in the solution obtained by melting frozen ice. The suboptimal intervals of the indicated parameters were the following: refrigerant boiling point 256– 260 K, blood consumption (0.20–0.205)·10-3 m3/s, dry matter content 22.5–23.0 %.